Shifting device for the swiveling of cars



Jfian- 1963 K. WINKLER SHIFTING DEVICE FOR THE SWIVELING 0F CARS 2Sheets-Sheet 1 I INVENTOR ,(aer MA/KL 52 g; M A zlvsrsn Filed March 1'7,1960 Jan. 15, 1963' K. WINKLER SHIFTING DEVICE FOR THE SWIVELING OF CARSFiled March 17, 1960 2 Sheets-Sheet 2 R ma M MM; M a A r Z J 04 VA/ mw m0% United States Patent 3.073.408 SHIFI'ING DEVICE FOR THE SWIVELING FCARS Kurt Winkler, Mallingerstrasse 69, Baden, Switzerland Filed Mar.17, 1960, Ser. No. 15.638 Claims priority, anplicationGermany Mar. 25,1959 4 Claims. '(Cl. 180-1) This invention relates to an improved devicefor shifting an automobile sidewise by a swiveling movement, preferably,about the bisecting point of an axle.

In modern city traffic the question of parking cars is of constantlyincreasing importance. Between cars parked in a row certain largeintervals must be maintained to permit the individual cars to enter andleave. Frequently there are gaps in the row which are only a littlelarger than the car itself and which can, therefore, not be utilized.Or, the car must be operated several times back and forth until itstands on the desired spot, which situation is associated with thedanger of damaging the already parked cars and the maneuvering car andwith a loss in time. other occasions, for example, when trucks are to beloaded or unloaded in front of a building.

The most expedient remedy for these dilficulties is a device which makesit possible to move the car approximately in a right angle to thedirection of driving. Many solutions heretofore have been suggested butnone of them has proved very practicable. Most of them are based on theidea of lifting the car and shifting it laterally by means of a pair orpairs of small auxiliary wheels or turning it about a fulcrum. Apartfrom the complicity and resulting susceptibility to'troubles which areinherent in all these devices, they are operable practically only oneven ground. Many modern roads are curved Similar problems are alsoencountered on' (crowned), however, to allow rain water to flow off.

rapidly, and hence they have a considerable inclination toward the edgeof the road. In most cases that occur in practice, therefore, theparking device must move the car uphill or downhill. It was found thatthe auxiliary wheels of the known devices have a much too small bearingsurface. Even with a slight additional work increase or a reduction ofthe coetficient of friction they glide on the ground without gripping.The inclination of the road edge can suffice to bring the downwardmotion of the car out of the control of the driver or--when attemptingto leave the parking spaceto prevent the upward motion. In addition, ifthe road should be Wet or icy the danger of sliding down increases, andit is impossible to move the car uphill, that is, from the edge towardthe center of the road. The same phenomena appear on inclined terrain,on snow, on soft or sandy ground and even with relatively smallobstacles or unevennesses in the path of the auxiliary wheels.

These difficulties are further increased by the fact that in themajority of all parking, swivel or turning devices for cars, the driveis effected by the car engine, requiring a complicated design. Thisdifficulty is attempted to be remedied by driving only half theauxiliary wheels, frequently only a single Wheel. The result of thisinsufficient drive is that the car becomes completely unmaneuverable ina much shorter time.

It has to be mentioned that most of these devices are subject to greatfouling and have no protection against it. It will be seen, therefore,that they are unsuitable for practical use.

In order to avoid the above mentioned disadvantages the need arises fora device for shifting cars where the bearing surfaces are large enoughpositively to prevent sliding on the ground in practically all cases andto ensure the maneuverability of the car under all weather-- 3,073,408Patented Jan. 15, 1963 and road-conditions. This requirement is met bythe shifting device according to the invention for the swiveling of carsin cooperation with a lifting device which--in operating position-liftsa pair of wheels of the car off of the ground. It is characterized by atleast two conveyor rolls, arranged in at least one vertically moveableframe, which conveyor rolls lie in a horizontal plane and can be drivenat will in both directions, but in each case in the same direction ofrotation.

The invention is represented schematically in the attached drawing inseveral non-limitative embodiments, the same parts being designated withthe same reference numbers, in which drawing:

FIG. 1 shows the retracted shifting device and its arr'angement in theautomobile, seen from the rear;

FIG. 2 shows the same shifting device in a plan view;

FIG. 3 shows the extended device, the rear wheels of the automobilebeing lifted from the ground;

FIGS. 4 and 5 shows various arrangements of the conveyor rolls in a planview;

FIG. -6 schematically shows the spring support of a conveyor roll on theframe of the shifting device, means for driving the conveyor roll beingomitted for simplicity.

FIG. 7 is an enlarged view of the device as shown in FIG. 1, but addingthe vehicle spring suspension and showing the drive means associatedwith the conveyor rolls may drive the elastically supported rolls,

FIG. 8 is a bottom view of the device shown in FIG. 7, and

FIG. 9 is a further enlarged detail view of the lifting and drivedevices.

According to FIG. 1, the automobile rests on the wheels 1, the shiftingdevice 2 being in retracted position. On the car frame 3, are securedpressure cylinders 4 which are actuated hydraulically or pneumatically.The simplest way is to connect them to a system already existing in thecar. The shifting device secured on the cylinder is retracted andextended by loading and relieving the cylin der. For stability reasons,four cylinders preferably are provided; however, two are sufiicient.They can be replaced by any other mechanical, electric or other liftingdevice. I

On the pressure cylinders 4, is secured the frame 5 of the shiftingdevice in which the conveyor rolls 6, 6, are

' arranged parallel to the longitudinal axis of the car. They preferablyhave a profiled surface or any other surface providing a good grip.Their diameter is so dimensioned that they project far enough under theframe 5 easily to overcome obstacles such as stones or smallirregularities in the ground. They are driven, by means of a chain drive7, by an electric motor 8 whose direction of rotation is reversible, andto which electric current is fed from the dynamo or the battery of thecar (not illustrated). Preferably, the electric motor 8 is arranged inthe frame 5 of the shifting device 2 between the con: veyor rolls 6 andoperated from the instrument panel of the automobile. Instead of thechain drive 7, there can also be used any other form of powertransmission, but the chain drive has proved resistant to fouling.

Sufiicient ground freedom is ensured with the shifting device retracted,since it can be made fiat.

FIG. 2 shows the same shifting device in a plan view, where the liftingdevice has been omitted for claritys sake. In the present example theshifting device is arranged directly behind the dilferential 9, becauseit can be accommodated there very easily. It can, however, also bearranged at any other locus.

FIG. 3 shows a similar shifting device to that il1ustrated in FIGS. 1and 2, but in extended position. It is supported on the ground, but withonly about half the car weight resting on it, while the pair of wheels 1of the car are lifted from the ground. In this embodiment, also theconveyor rolls 6 are driven by the electric motor 3 by way of a chaindrive 7, but they have here an additional function. They must move theself-contained conveyor belt It? which is wrapped about both of them. Inorder to ensure the necessary bearing surface and the desired bearingpressure for the conveyor beltwhich can be an endless belt of knowndesignit can be pressed against the ground in addition by auxiliaryrolls 11, which are arranged between the conveyor rolls but are notdriven. Additional auxiliary rolls 12 serve to guide and stretch theunloaded portion of the conveyor belt. Such a belt has an advantage overthe conveyor rolls represented in FIG. 2 if the road conditions areparticularly adverse. In this case, it may also be expedient to supportthe two outermost rolls a little higher than the others, so that they nolonger bear on the ground. This applies both to the conveyor rolls andto auxiliary rolls arranged outside these rolls. With this arrangementobstacles are easier to overcome.

If two shifting devices are provided in a car and it can thus be shiftedparallel to its longitudinal axis, the conveyor rolls, or the conveyorbelt surrounding them, roll or rolls smoothly on the ground. A differentsituation is presented if only one shifting device is provided whichlifts, for example, the rear wheels while the car rests on its frontwheels. If the rear part of the car is now shifted, the movability inthe axle journals of the front axle results in a big turning circlewhose center lies approximately in the point of bisection of the frontaxle. The conveyor rolls or the conveyor belt now can no longer roll offsmoothly. They tend to run straight, but are forced to described an arc.The result is a displacement of these conveyor elements on the ground sothat a combination of rolling and sliding friction results m aresistance against the motion. This requires more power for the motionand results in a greater wear of the conveyor rolls or of the conveyorbelt.

In order to avoid these disadvantages, the conveyor rolls 13 are soarranged according to FIG. 4 that they run on a turning circle whosecenter M lies approximately in the point of bisection of the unliftedwheel axle 14 of the car. In this way the rolls 13 can roll off on theturning circle, and there is only a slight displacement on the groundtoward their ends. If this insignificant error is also to be avoided,the conveyor rolls 13 must be provided with a conicity which correspondsto the radius of the turning circle, that is, the apex of the cone liesin the center of the turning circle. With this form, the conveyor rollsmove exactly on their rolling circle, and the lateral resistance on theground is reduced to a minimum.

Another variant for the arrangement of the coveyor rolls is shown inFIG. 5. The rolls 15 run in pairs on a turning circle whose center Mlies approximately in the point of bisection of the unlifted wheel axle14 of the car, and their symmetry axes 16 point to the center of theturning circle: in each pair, the axes of the rolls are parallel to eachother. The advantage lies in the greater number of conveyor rolls, whichresults in an increase of the bearing surface and of the adhesionwithout complicating the drive, since the rolls can be driven in pairs.It is also possible to surround each pair of rolls 15 with a conveyorbelt 17, as it is shown in FIG. 5, with one pair of rolls so enveloped.This arrangement combines the advantages of the conveyor belt with anarrangement wherein the conveyor rolls run on a turning circle.

in order to make the entire driving mechanisms of the shifting devicemore elastic, it is of advantage to support all conveyor and auxiliaryrolls on springs, as is represented schematically in FIG. 6, forexample.

FIGS. 7, 8 and 9 illustrate one way that'the drive means may beassociated to drive the elastically supported rolls 19. The end bearingscarried by shafts 18 are linked to move substantially vertically withinthe frame 5,-and are pressed downwardly by suspension springs 2% whichdistribute the load of the roll between them. Each s ring, however, isdesigned so that it will carry the entire load of the corresponding rollwithout retracting the roll entirely into the bottom of the frame 5.

The means for locking the wheel suspension in its loaded position asillustrated diagrammatically in FIG. 3 may be constructed as shown inH6. 7 where the parts are numbered the same way, and the levers 23 arenormally moved to inoperative position by the rods shown extendingfoiwardly therefrom, and may be released into operative engagement wtihthe lugs 22, when desired, for lifting the wheels with the frame.

Under normal load the shafts 13, of the conveyor roll 19, which aresupported in the frame 5 of the shifting device, are pressed down bysprings 28 on their hearing seat. If the load increases, the springsyield upwtrd, and the weight remains distributed over all rolls. Thishas the effect that the car is not lifted and lowered again every timeit rolls over a stone, for example, as soon as one roll passes over theobstacle and it has to carry the whole weight. In this embodiment,conveyor roll 19 is driven in the manner described hereinabove.

It is of advantage to provide a tensioning device for each chain driveand for each conveyor belt, and to equip each shifting device with aself-locking or loci:- ing device to prevent the car from overspeedingon steep slopes. The number of conveyor rolls or pairs of conveyor rollsis not limited to two in all models, just as it is possible on the otherhand, to divide the frame and to provide a conveyor rollor, a pair ofconveyor rolls-- in each section, so that the device can be housedeasier in the fenders, for example, or in the rear tins of the car. Insome cases it may be of advantage to replace this divided frame by afork or a similar roll-holding device.

As shown in FIGS. 1 and 3, the shifting device is normally secured onthe car frame 3 whose lifting also effects the lifting of the car. Whenthe shifting device reaches the ground during the lowering of the same,the wheels 1 of the car are not yet lifted. They remain on the ground solong until the car frame has been lifted by the considerable travelstroke of the car springs (not illustrated). Only when they arecompletely relieved, are the wheels lifted. This difficulty can beavoided if the car springs are locked in their loading position, duringthe lifting and turning operation.

A device of this type is represented by way of example in FIG. 3. Acatch 22 is rigidly connected with the rear axle 21. On the car frame 3there is articulated a lever 23, which lever is held out of engagementby a spring 24. By suitable means (not shown) the descending shiftingdevice 2 presses the lever 23, against the spring force, into the catch22 and retains it there. When the wheels 1 are lifted from the ground,they can not relax the car springs, since the car springs remain lockedin their loaded position. When the shifting device 2 is retracted againand the wheels I touch the ground the car weight loads the car springs,the lock is released, and the spring 24- forces the lever 23 out ofengagement as soon as the shifting device clears the path.

The turning process takes place, for example, as follows: In order topark a car in the gap within a car row, the car is driven into the gapwith the front wheels first. Care has to be taken that the front wheelsas far as possible come to stand on their proper spot. After braking thefront wheels, a button on the instrument panel is pushed which acts on ashut-off valve in the feed line to the pressure cylinders. The valveopens and the pressure cylinders extend the shifting device arrangeclose to the rear axle. During this process the spring suspension of thewheels is locked in its loaded position by an automatic device. Theshifting device touches the ground, the rear wheels are lifted and thecar weight rests on the front wheels and on the shifting device. Bythrowing a toggle switch on the instrument panel in the desireddirection, the electric motor of the shifting device 5 is set inoperation which in turn sets the conveyor rolls in operation. The rearpart of the car is swung about until it stands on the desired spotwhereupon the motion is stopped by returning the toggle switch to itszero position. The moving axle journals of the front axles have afavorable effect, because they permit a long turning path of the carWithout the front wheels having to move from their spot. By pushing asecond button on the instrument panel, the pressure cylinders arerelieved, the

shifting device is retracted, the lock is released and the car standsagain on its four wheels.

The electric motor is locked electrically. It can only be started whenthe shifting device is completely extended. Likewise, the pressurecylinders can not be re lieved as long as the electric motor is running.

The shifting device according to the invention permits utilization ofeven relatively small gaps in a row of parked cars, and to park the carsmuch closer together, which is a great advantage not only in parkinglots but also in garages. The device is also useful when changing tires,since it can make a jack superfluous.' Other advantages result, forexample, whena car is stuck in anuneven terrain, or when the engine hasbecome unservica able due to an accident, or when the wheels areblocked.

In these cases, just as in narrow curves, it is frequently desirable toshift the car laterally. The usability on any terrain found in practiceand at any weather, the security against gliding or overturning onsloping ground and the resistance, aganist fouling and irregular loadmake the shifting device according to the invention an important part ofthe car.

I claim: 1. A shifting device for swivelling an automobile having avehicle frame and front and rear wheels, comprising a lifting devicehaving its upper end fixed to one end of said vehicle frame between thecorresponding wheels, a swivelling drive device having a frame structurefixed to the lower end of said lifting device, said swivelling drivedevice being normally held off the ground and lowered to the ground byoperation of said lifting device to raise said corresponding wheels offthe ground, I V said swivelling drive device including at least two conbearing and its upper end abutting said frame structure, whereby saidrolls will maintain a sulficiently extended surface contact with theground to provide good traction on soft and variably inclined roadsurfaces, 7

and reversible power means mounted in said frame structure and aflexible belt drive means drivably connecting said conveyor rolls andsaid power means to drive said rolls at will in either direction.

2. A shifting device as defined in claim 1, the corn veyor rolls havingthe axes operating in substantially vertical planes radiating from avertical axis midway between said wheels at the other end of saidvehicle frame.

3. A shifting device as defined in claim 2, said conveyor rolls beingprovided with a conicity the apexes of which lie in said vertical axis.

4. A shifting device as defined in claim 1, and means for locking thewheel suspension at said one end of said vehicle frame in its loadedposition to said vehicle frame during said lifting and swivellingoperations.

References Cited in the file of this patent UNITED STATES PATENTS GreatBritain July 1924

1. A SHIFTING DEVICE FOR SWIVELLING AN AUTOMOBILE HAVING A VEHICLE FRAME AND FRONT AND REAR WHEELS, COMPRISING A LIFTING DEVICE HAVING ITS UPPER END FIXED TO ONE END OF SAID VEHICLE FRAME BETWEEN THE CORRESPONDING WHEELS, A SWIVELLING DRIVE DEVICE HAVING A FRAME STRUCTURE FIXED TO THE LOWER END OF SAID LIFTING DEVICE, SAID SWIVELLING DRIVE DEVICE BEING NORMALLY HELD OFF THE GROUND AND LOWERED TO THE GROUND BY OPERATION OF SAID LIFTING DEVICE TO RAISE SAID CORRESPONDING WHEELS OFF THE GROUND, SAID SWIVELLING DRIVE DEVICE INCLUDING AT LEAST TWO CONVEYOR ROLLS OF SUBSTANTIAL LENGTH DISPOSED IN AND PROJECTING BENEATH SAID FRAME STRUCTURE, EACH OF SAID CONVEYOR ROLLS BEING SUPPORTED ON AXLES AND BEARINGS AT ITS ENDS, AND HAVING ITS AXIS IN A SUBSTANTIALLY HORIZONTAL PLANE, A COIL SPRING FOR EACH END BEARING HAVING ITS LOWER END ABUTTING SAID END BEARING AND ITS UPPER END ABUTTING SAID FRAME STRUCTURE, WHEREBY SAID ROLLS WILL MAINTAIN A SUFFICIENTLY EXTENDED SURFACE CONTACT WITH THE GROUND TO PROVIDE GOOD TRACTION ON SOFT AND VARIABLY INCLINED ROAD SURFACES, AND REVERSIBLE POWER MEANS MOUNTED IN SAID FRAME STRUCTURE AND A FLEXIBLE BELT DRIVE MEANS DRIVABLY CONNECTING SAID CONVEYOR ROLLS AND SAID POWER MEANS TO DRIVE SAID ROLLS AT WILL IN EITHER DIRECTION. 